Wrap asgi application to ignore lifetime requests

ASGI servers send "lifetime" requests to django at startup and shutdown.

The ASGI spec allows these to fail, in which case the server ignores them, however
the way django fails them sends an exception to sentry which we don't want.

Overwrite the handler to return a 501 error without throwing an exception

posthog/asgi.py

@@ -1,8 +1,21 @@
 import os
 
 from django.core.asgi import get_asgi_application
+from django.http.response import HttpResponse
 
 os.environ.setdefault("DJANGO_SETTINGS_MODULE", "posthog.settings")
 os.environ.setdefault("SERVER_GATEWAY_INTERFACE", "ASGI")
 
-application = get_asgi_application()
+
+# Django doesn't support lifetime requests and raises an exception
+# when it receives them. This creates a lot of noise in sentry so
+# intercept these requests and return a 501 error without raising an exception
+def lifetime_wrapper(func):
+    async def inner(scope, receive, send):
+        if scope["type"] != "http":
+            return HttpResponse(status=501)
+        return await func(scope, receive, send)
+    return inner
+
+
+application = lifetime_wrapper(get_asgi_application())